Both an orthogonal frequency division multiplexing (OFDM) waveform and a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM) waveform are typical waveforms in wireless communications. The OFDM waveform can be used to provide a higher capacity in a scenario in which a signal-to-noise ratio is high, and is applicable to a cell center user. In contrast, the DFT-S-OFDM waveform characterized by a relatively low peak-to-average power ratio (PAPR) can be used to provide a wider coverage area, and is applicable to a cell edge user with limited coverage.
Currently, the new generation wireless communication (NR) standard of the 3rd Generation Partnership Project (3GPP) stipulates that both the OFDM waveform and the DFT-S-OFDM waveform are used in an uplink for data transmission. Correspondingly, a terminal device needs to support both the OFDM waveform and the DFT-S-OFDM waveform, and a network device needs to obtain power headroom (PH) information of the terminal device when data is transmitted by using the OFDM waveform and obtain PH information of the terminal device when data is transmitted by using the DFT-S-OFDM waveform, so that the network device implements resource scheduling and power control for the terminal device based on the two types of PH information. PH is defined as a difference between a maximum transmit power of the terminal device and a calculated configuration transmit power of the terminal device.
However, in a scenario in which both the OFDM waveform and the DFT-S-OFDM waveform are used in the uplink for data transmission, currently there is no method for obtaining the two types of PH information by the network device.